1. Field of the Invention
The present invention relates to a portable computer and a controlling method thereof, and, more particularly, a portable computer, and a controlling method thereof, which can reduce power consumption by interrupting the supply of power driving a display panel when a display is closed even if the low-power state is not configured.
2. Description of the Related Art
A general portable computer comprises a main body provided with a keyboard, a Floppy Disk Drive (FDD), etc., and a display attached by a hinge to the main body so as to open and close. Commonly, the display of the portable computer incorporates a flat display panel such as a Plasma Display Panel (PDP), Liquid Crystal Display (LCD), etc., which makes the portable computer easy to carry.
Such a portable computer is operated using electric power supplied from a DC adapter or a battery. However, when the portable computer is operated using the battery-supplied electric power, the allowable operating time is restricted to the battery life. Therefore, in order to extend the limited battery life and maximize the allowable operating time, accordingly achieved by the reduction in power consumed, various power saving measures have been proposed.
FIG. 6 is a flowchart illustrating a conventional power control when a display of a portable computer is closed.
Referring to FIG. 6, at operation 101, if the display of the conventional portable computer is closed, at operation 102 a driving power for a back-lit unit is interrupted. At operation 104, a MICOM (MIcro COMputer), a BIOS (Basic Input Output System), and an O/S (Operation System) sequentially determine whether the display of the portable computer is closed or not. Thereafter, a power management program in the O/S reads out a predetermined power state according to the closure of the display at operation 106, and places the portable computer into the power state corresponding to the predetermined power state at operation 108.
Herein, in a case in which the power state is set to a low-power state such as S3 (one level of standby in which minimal power is maintained) or S4 (hibernation), the O/S places the portable computer into the low-power state to achieve the reduction of power use.
Meanwhile, in a case in which the power state is not set to the low-power state, for example, S0 (fully active), S1 (another level of standby in which the display and drives are powered off), etc., only the driving power for the back-lit unit is interrupted.
Therefore, the driving power for the display panel is maintained and consumed even if the display of the portable computer is closed, that is, even if a user does not use the display for a while, although the portable computer does not need to supply the driving power for the display panel.